The present invention relates to an improved EMI/RFI shielded, two part container for components such as circuit boards and the like.
Modern miniaturized electronic components are sensitive to damage from physical shock, vibration, and external electric fields such as static electric fields and EMI/RFI fields. Either physical shock or such electric fields, if not controlled, can decrease the effective life or even destroy the function of the component.
Such potentially damaging external electric fields can be generated at many stages in the development, production, and shipment of electronic components such as circuit boards. Static electric fields can be generated whenever two objects come in contact with one another and are then separated. EMI/RFI fields can be generated by static discharges or by transmitters of various types.
A number of approaches have been used in the past to protect electronic components from external electric fields. EMI/RFI bags and pouches have been used, in which the bag or pouch is sealed around the electronic component, and then placed in a cushioned box for required physical protection. Closure of the EMI/RFI bag can present difficulties, and EMI/RFI protection varies in accordance with the effectiveness of the seal. Each time an EMI/RFI bag is opened, it must be replaced or resealed in order to maintain EMI/RFI protection.
Another approach of the prior art is to use permanent metal containers or metal lined containers. Such containers may provide effective sealing and EMI/RFI protection. However, the cost of such containers may be prohibitive for many applications.
Another approach is to provide shielded shipping containers. U.S. Pat. Nos. 4,160,503, 4,308,953, and 4,480,747 provide three examples of such containers. These containers may work well depending upon the specific design of the container and its conductive surfaces. Nevertheless, a need exists for an improved multiple part container which combines excellent physical protection to the electronic component along with excellent DC and static field and EMI/RFI shielding.